Spray gun



Oct. l, 1929. T BIRKENMAlER 1,729,759

SPRAY GUN lFiled Sept. 13, 1926 Patented Oct. 1929 UNITED STATES PATENT OFFICE THEODORE BIRKENMAIER, OF ST. LOUIS, MISSOURI, ASSIGNOR TO W. MATTHEWS CORPORATION, OF ST. LOUIS, MISSOURI. A CORPORATION OF MISSOURI SPRAY GUN Application filed September 13, 1926. Serial No. 135,113.

This invention relates to spray guns for paints, lacquers and the like, and with regard to certain more specific features to an improved spray gun nozzle and linkage for operating the same. t v

Among the several objects of the invention may be not-ed the provision of an improved type of nozzle, whereby the quantitative functioning of the several elements of a spray gun may be varied without changing many or costly parts; the provision of the above improved features Which involve no disconnections of supply lines to the gun when changes are made; the provision of a nozzle of theuclass described which is simple in operation and rugged in construction, not being readily subject to derangement; and the p rovision of a gun of the class described which is provided with a rugged and readily operable auxiliary adjusting means. Other objects will be inpart obvious and in part pointed hereinafter.

The invention accordingly comprises the yelements andconibination of elements, features of construction, and arrangements of parts which will be exempliiied in the structure hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings, in which is illustrated one of various possible embodiments of the invention,

Fig. 1 is a longitudinal section of the gun showing certain elements in full;

Fig. 2 isan enlarged longitudinal section of the nozzle of the gun shown in Fig. 1;

Fig. 3 is an enlarged plan view of a springl ring; y

Fig. 4 is a cross section taken on line 4.-4 of Fig. 2;

Fig. 5 is a cross section taken on line 5,-5

of Fig. 2; and

Fig. 6 is a front elevation of the nozzle shown in Fig. 2. l

Similar reference-characters indicate corresponding parts throughout the several views of the drawings.

Rreferring now more particularly to Fig. l, there is illustrated at numeral 1 a body provided with an air passage 3, and a material passage 5.. An inlet pipe 7 communicates with the rear ortion of the air passage 3 and, by means o a nipple 9, holds a suitable hand grip 11 in place beneath a guard 13 on the body 1. The nipple 9 is adapted to have a flexible air line coupled thereto for supplying compressed air to the passage 3.

A second nipple 15 which intersects but does not block the passage 3, communicates with and is adapted to supply material to the material passage 5. A flexible material line is adapted to be fastened to this nipple 15'. The material is usually a liquid such as a paint, a lacquer or the like.

`The rear portion of the air passage 3 is counterbored and provided with a seat 17 for receiving a spring seating control valve 19. The valve spring reacts against a bushing 21 which functions as a slide bearing for the stem of the valve and also as a packing box for receiving a packing 23 and a gland 25. They outer end of the valve 19 is provided with a threaded locking nut 27 and a threaded adjustable nut head 29 to be locked thereby. The head 29 slidably cooperates with a saddle member 31 which is pinned to ae trigger 33. The-trigger 33 is pinned to an extension 35 of the body 1. lIt is evident that the rearward pressure on the trigger 33 will result in opening the valve 19 to permit air to flow into the passage 3 and the spring tension in the valvetends normally to return the trigger. The amount of valve opening for a full trigger action may be regulated by regulating the head 29 to give more or less elfective trigger action. Regulation is accomplished when the gun is assembled.

A nipple 37 (Fig. 2) is screwed into the forward end of the materia-l passage 5 and is bored to form a continuation of said passage. This nipple 37 is provided with`r an internal valve seat 39 for receiving and seating a beveled valve 41. The valve V41 has a stem 43 provided with slidable spacing guides 45. This stem 43 extends rearwardly through the passage 5 and is slidably supported at the rear of Said passage by a gland assembly 46 similar to the one described in connection with the valve 19. The end of the CII spring 53 normally acts to seat tlfe material valve. Some play is left between the head 47 and the trigger camming port-ions '51 when the air valve 19 is about to be opened by the saddle 31. In this way the air is always turned on an instantv before theliow of material starts, that is, as the trigger 33 is ulled.

manually adjustable screw 54 is provided rearwardly `of the stem 43 for engagement with said stem, to limit the opening which may be given to both vJvalves 19 and 41. `The above described structure provides means for changing the amounts of opening of either valve-wlth respect to the other (adjustment accomplished upon assembly), and also lfor limiting at once the amount of opening of boththe valves (adjustment accomplished during use by screw `54). An opening 55 in -the lug 35 provides means for readily hanging the gun up. A clean-out plug and cooperating passage (combination 57) is' prol vided on one side of the material passage 5.

The nozzle elements of the gun comprise a barrel 59 which includes a crater face piece 61; The face piece is made separate for purposes of disassembling with a View to facilitating cleaning and assembly but otherwise these pieces may be considered as one element, that is, a barrel having a crater face. l

The barrel 59 is held to the body 1 by rings 62, 63' which are tightly forced together so .e as to rotatably engage a flange 65 on said barrel. This is because a flange 67 on the ring 63 stops the pressed on ring 61, at a pos1- tion predetermined to give a sl1ght clearance aroundv said flange 65. The ring 63 is internally threaded' to cooperate with threads on the body 1, whereby a swivel nut N is formed to `control the long1tudinal movements of the barrel 59 with respect to the'body 1.. .The swivel nut N comprises the tightly joined.

:narily ,for app ying a wrench -tfscrew the nipple. 37 home) holds the ring'77 ofthe nose 79 when the barrel 59 is removed.

Otherwise (when the barrel is in position on the cylinder 75) the ring 77 is held flatly face to face with the flat bottom of the lirst depression 69. It is so held by the pressure exerted behind it by a convoluted spring ring 81 (see Fig. 3). A dowel pin 83 held to the ring 77 and passing through an opening 85 in the spring ring and 4slidably into a hole 87 in the cylinder holds the ring 77 and spring 81 in predetermined angular positions with respect to said cylinder75 but permits endwise movement of both.

By the above means, an annular space 89 is left between the ring 77 and the nose 79. Pairs of holes 91, 93 are drilled through the ring from front to rear on ninety degree vertical and horizontal lines (see Fig. 4). The

bottom hole 91 aligns with a hole 95 in the spring ring 81 and with said air passage 3 in the gun body 1. Pairs of radial slots 97, 99 are cut across the pairs of holes 91, 93 respectively and in the front engaging face of the ring 77.

A. pair of oppositely spaced passages 101 lead through the barrel 59 (including its face piece 61) in such a manner as to be aligned with either of the sets of holes 91 or 93 when positioned vertically or horizontally respectively, and to eject air from the crater face 108 of the barrel forwardly and angularly as shown by the arrows in Fig. 2. In other positions of the barrel 59 the passages 101 are out of communication with any air supply because their rear ends are llat against the face of the ring 77. Reduced portions 102 at the rear ends of the passages, which are smaller in bore than the outlets of the passages at said crater face 108, serve to throttle the air before it reaches said outlets of the passages 101, whereby a smooth flow of auxiliary air leaves these passages. This gives the gun what is known as a velvety action.

, The second recess 71 of the barrel 59 is for .the purpose of accommodating said flange and a stop flange 103 of a bushing 105, which is tightly forced into the main body member of the barrel 59 at the said recess 73. This bushing 105 is provided with longitudinal air scribed, this bushing moves with respect to the nipple 37.

The central bore of the bushing 105 is provided with a 'forward bevel 109 which is adapted to seat on a forward outside conical portion 111 of the nipple 37 From the bevel 109 extends a supplementary material nozzle 113 which is annularly spaced with respect to an air nozzle-1l5 formed in and from the crater face 108. The outer end of the air nozzle 115 extends a short distance from the member 61 and the outer end of the material nozzle 113 extends a few thousandths of an inch ahead of the outer end of said air nozzle.Y A communicating passage 117 joins the air nozzle 115 with said longitudinal air passages q107.. From the above, it will be seen that the supplementary material nozzle :113 (a portion of bushing 105) cooperates with the material outlet in liquid-tight fashion` to extend said outlet.

The said valve 41 is provided with a cleaning ram 119 which passes through the outlet opening 36 of the nipple 37 and 1nto and through the opening of the material nozzle 113. The purpose of the ram 119 is to prevent any material which might dry 1n the nozzle 113 A(while. the gun is not in use) from completely closing the passage; Hence when the gun is again used, the withdrawal of the ram 119 will provide an open passage which, even though there be some dry material therein, will very shortly be completely cleared by the flow ofu material from the mpple 37.

The operation of the gun is as follows:

A pressure air line is joined to the nipple 9 under the handle of the gun and a material line (preferably under pressure) is joined to the nipple 15. If it is desired to form a noncircular target of paint, that is an oval shaped target, thebarrel 59 is set to some position such that its two passages 101 are vertically or horizontally arranged. This means that lthese two passages 101 are aligned with the pairs of openings 91 or 93 in the cut-off. ring 77. lf a horizontal fan shape of spray 1s desired, these passages 101 are vertically arranged and if a vertical fan shape is desired these passages are horizontally arranged.

If the passages 101 are assumed to be in their vertical position as illustratedin Fig. 2 and the trigger 33 pulled back, the first action will be to admit air into the passage 3, because the valve 19 opens first as hereinbefore described.

The air flows from the passage 3, through the opening 95 in the spring ring 81, in behind the ring 77 and info the annular space 89. If the spring 81 is compresed so as to admit little air behind the ring 77, then air will get to the annular passage 89, by way of the lower hole 91 in the ring 77 and the slot 97 associated therewith. The slots 97 and 99 rovide means whereby air may be positive y communicated to the passages 101 when they align with a pair of the holes 91 or 93, regardless of how the spring ring 81 is compressed.

Air also flows from the annular passage 89 and the slots 97, 99 into said second def pression 71 of the barrel 59. From this defpression the air flows through the longitudinal air passages 107 into the annular air nozzle 115. From the above it is evident that an annular column of air is ejected from thev nozzle 115 around the material nozzle 113 and auxiliary jets of air impinge from the passages 101 on this annular column, whereby the column is somewhat flattened to a more or less elliptical fan shape. The conical shape of the column of air from the annular nozzle 115 prevents'piling up of air in the central column of air behind the jets from the y sideward columns.

An instant after the air begins to flow, as above described, the camming portions 51 en-V gage the head 47 to open the material valve 41. YAny dried or other material which may be positioned in the material nozzle 113 is broken open When'the ram 119 moves rearwardly. The material flows from the passage 5, through the nipple 37, out of the opening therein and is ejected from the material nozzle 113 in a thin cylindrical column. The nozzle is soon cleared if it was dirty. As the material leaves the'nozzle 113 the ejection thereof is aided by the aspirating action of the air from the nozzle 115. This air also breaks up the material into a fine s ray or mist. Next, the spray thus forme is impinged upon by the auxiliary sideward air columns to be shaped elliptically or as a fan.`

When the trigger 33 is released 'the material valve is closed off first. The fact that the air starts flowing first and stops flowing last results in practically always clearing away any residue paint from the nozzle 113 whereby undesirable dripping or spurting of undividedmaterial is prevented. Flowing air is always present before and after the material.

When it is desired to change the position of the ellipse or fan from horizontal to vertical, the trigger 33 is released to shutoff all flow, the swivel loosened and the barrel 59 turned through ninety degrees so "that the passages 101 align with the holes 93 in the ring 77 If a cone shaped spray is desired without an-ellipticalV or fan shape, then the same operation is performed except that the barrel 59 is not turned to a ninety degree position. After the barrel 59 has been adjusted, it is always drawn up again by means of the swivel nut N so that the bevel 109 seats on the conical end 111 of the nipple 37. One of the advantages of this gun is that lthe material nozzle 113 is not an integral portion of the nipple 37 which supplies material ,to the nozzle. It is rather a portion of the barrel 59 and is applied by assembling to said nipple 37. This means that a manufacturer of the gun may make a standard body l including all of its auxiliaries such as the air and material valves, passages, leads to these passages and the rings 77, 81. Then the barrel 59, including its crater face 61'and bushing 105, may be applied separately achieved and other able among themselves and on the gun body 1, but are made up so that different sizes of annular spaces are had between the nozzle 113 and 115 and also different sizes of central openings in the material nozzle 113. The exact shapes of the nozzles 113 and 115 may also be readily varied.

The result of the above is that themanufa'cturer may at small expense supply the user With means for instantaneously changinor the spraying characteristics and capacity o his gun. Furthermore,`the user may have several of the nozzle assemblies on hand and if a change is desired the trigger 33 needs merely to be released, and one nozzle assembly replaced for another. This has the great advantage of not requiring unfastening of the flexible supply line from the nipple 15. The use of a crater portion 61 separate from the barrel portion 59 proper, results in greater ease in cleaningthe passages lOland also in the possibility of a manufacturer-carrying various sizes of the material and air nozzles which may be assembled in various combinations as users call for them.

In view of the above, it Will be seen that the several objects of the invention are advantageous results attained. n

As many changes could be made in carrying out the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim: 1. In a spray gun, a body, a material passage therein andan air passage, a nipple communicating with the material passage and a valve therein, a valve in said air pasy sage, a nozzle assembly movably fastened to the body carrying a material nozzle and an air nozzle, said material nozzle being adapted to cooperate with said nipple to receive. material therefrom and eject it into the air moving from said air nozzle.

2. In afspray gun, a body, a material passage therein having an outlet, a nozzle assembly removably and adjustabl fastened to the body and not including said outlet but carrying a supplementary material nozzle which is adapted to cooperate With said outlet in liquid-tight fashion to extend it.

3. In a spray gun, a body,` a material passage therein and an air passage, a nipple communicating with the material passage and a/ valve therein, a valve in said air passage,

a separate nozzle assembly movably fastened to the body carrying a supplementary material nozzle and an air nozzle in fixed and predetermined relationship, said material Anozzlebeing/adapted to cooperate with said nipple in liduid-tight fashion .to extend it vand a ram on said valve in `the material passage 4. In a spray gun, a body, a material passage therein, an outlet for said passage having a. valve therein, a separate nozzle assembly removably and adj ustably fastened to said body carrying a supplementary material nozzle and an annular air nozzle surrounding the same in fixed relationship, said material nozzle being adapted to cooperate With said supplementary outlet to form a materia carrying extension thereof.

5. In a spray gun, a body, a. material passage therein, an outlet for said passage having a Valve therein, a separate nozzle assembly removably and adjustably fastened to said body carrying a supplementary material nozzle and an annular uair nozzle surrounding the same in fixed relationship, said material nozzle being adapted to cooperate with said outlet to form a material carrying extension thereof and a ram on said valve adapted to pass into said supplementary material nozzle.

6. In a spray gun, a body, a material passage therein, an outlet for said passage having a valve therein, a nozzle assembly relnovably and adjustably fastened to said body carrying a material nozzle and an air nozzle, said material nozzle being adapted to cooperate with said outlet, a cut-olf member resiliently held to said body to be pressed to a seat in the nozzle assembly, means for supplying. air to predetermined recesses in the cut-off member and auxiliary air passages in the nozzle assembly adapted to transmit said air to eject when the nozzle assembly is in predetermined positions. 4

' 7. In a spray gun, a body, a material passage therein and an air passage, a nipple communicating with the material passage and a valve therein, a valve in said air passage, a nozzle assembly movably fastened to the body carrying a Vmaterial nozzle and an air nozzle, said material nozzle being adapted to cooperate with said nipple and said air nozzle communicating with the air passage, said cooperation between the material nozzle and the nipple 'being adapted to keep theair and material passages out of communication, a cut-off member resiliently held to said body tobe pressed to a seat in the nozzle assembly, means for supplying air to predetermined recesses in the cut-olf member and auxiliary air passages in the nozzle assembly adapted to transmit said air to eject when the nozzle assembly is in predetermined positions.

8. In a spray gun,va"body a material passage therein and an air passage, a nipple communicating with the material passage' to cooperate with saidinipple, a ram on the material valve adapted to pass into the material nozzle, said air nozzle communicating with the air passage, saidrcooperation ybetween the material nozzle and the nipple being adapted to keep the air and material passages out of/ communication, a cut-off member resiliently held to said body to be pressed to a seat in the nozzle assembly, means `for`supplying air to `predetermined recesses in the cut-oii' member and auxiliary air passages in the nozzle assembly adapted to transmit said air to eject When the nozzle assembly is in predetermined positions?y 9. In a spray` gun, a body, a material passage therein and an air passage, a nipple communicating with the material passage and a 'valve therein, a valve in said air passage,l a

nozzle assembly movably fastened to the body carrying a material nozzle and a surrounding annular air nozzle, said material,

nozzle being adapted to cooperate with said nipple and said air nozzle communicating with the air passage, said cooperation between the material nozzle and the nipple being adapted to keep the air andmaterial passages out of communication, a cut-oil member resiliently held to said body to be pressed to a seat in the-nozzle assembly, means for' supplying air to predetermined recesses in the cut-0E member and auxiliary air pas.- sages in the nozzle assembly adapted to transmit said air to eject when the nozzle assembly is in predetermined positions.

10. In a spray gun, a body, a material passage therein having an outlet, a nozzle assembly removably fastened to the body andcarrying a material nozzle and an air nozzle in fixed relationship, the material nozzle eX- tending 'beyond the air nozzle, said material nozzle being adapted to cooperate With said outlet of the material passage to receive and t eject the material.

1l. In a spray gun, a body, a materlal passage therein having an outlet, an adjustable nozzle assembly fastened to the body and carrying a supplementary material nozzle and outlet air passages in a singleunit, said supplementary material nozzle engaging "said outlet to form a continuous extension for said material passage. c

12. In a spray gun,.a body, a material passage therein having an outlet, a nozzle assembly fastened to the body andvcarrying a supplementary material nozzle and outlet air passages in a single unit, said supplementary material nozzle engaging said outletJ to form a continuous extension` for said material passage. p y y In testimony whereof, I have signed my name to this specification this 9th day of September, 1926. THEODORE BIRKENMAIER, 

